Pick-proof lock



July 12, 1966 R. BoDl-:K ETAL 3,260,082

PICK-PROOF LOCK Filed Nov. 22, 196s Fig. 2

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. f /A SSW Ralph Bode/r Bennie A. DIF lavis l N VEN T0125 Y WWW 3%1United States Patent O 3,260,082 PICK-PROOF LOCK Ralph Botlek and BennieA. Di Flavis, Philadelphia, Pa., assignors to Bodek Enterprises, Inc.,Upper Darby, Pa., a corporation of Pennsylvania Filed Nov. 22, 1963,Ser. No. 325,548 s Claims. (01.70-421) The present invention generallyrelates to a lock which is of unique construction which renders the lockcompletely pick-proof and in addition informs the owner or others than'an attempt has been made to pick the lock or the lock has beenotherwise tampered with.

The lock of the present invention may be employed with various types oflocks for any Iuse for which a lock is normally intended. For example,the pick-proof lock construction of the present invention may beemployed in tumbler type locks having any number of pins. It may also beemployed in wafer-type locks or any other type of lock requiring the useof a key for operating the locking mechanism.

Basically, the structure of .the present invention enables a lock to beconstructed so that it cannot be opened by any known methods ofutilizing skeleton keys or lock picking .tools in use at the present.time and also, the lock, if tampered with such as by using a skeletonkey or any locking picking tool in an attempt to open it, the owner willknow immediately that some effort has been made to open the lock.

Another object of the present invention is .to provide a pick-proof lockconstruction which will, in effect, destroy itself upon insertion of animproper key or upon insertion of a lock picking tool thereby lockingthe movable components of the lock Ito preclude movement in anydirection even though .the proper key may be subsequently placed in thelock thereby serving to prevent the lock from being picked and at thesame time indicating to the owner of the lock or to a person having aproper key .that the lock has been .tampered with.

Yet another object of the present invention is to provide a pick-prooflock that is relatively simple in construction, capable of beingincorporated into existing lock structures with very little modificationthereof, dependable -and long-lasting in operation, fool-proof insofaras preventing picking thereof is concerned and relatively inexpensive tomanufacture.

These together with other objects and advantages which will becomesubsequently apparent reside in .the details of construction andoperation as more fully hereinafter described and claimed, 4referencebeing had to .the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout, and in which:

FIGURE 1 is a sectional view of the lock construction of the presentinvention illustrating the pick-proof construction incorporated thereinwith a proper key inserted;

FIGURE 2 is a transverse, sectional View taken substantially upon aplane passing along section line 2-2 of FIGURE 1 illustrating theorientation of the floating cylinder pin and corresponding frictionallyretained tumbler pin illustrating the juncture coincident with the shearline between the barrel and cylinder;

FIGURE 3 is a sectional view similar to FIGURE l but illustrating animproper key inserted into the lock and illustrating the position of thefloating cylinder pin and .the frictionally retained tumbler pin whichprecludes rotation of the barrel;

FIGURE 4 is a transverse, sectional view taken substantially upon aplane passing along section line 4 4 of FIGURE 3 illustrating furtherrelationships between the pick-proof construction of the presentinvention when an improper key is inserted;

FIGURE 5 is an exploded group perspective view illustrating theconstruction of the frictionally retained tumbler pin and the structurefor frictionally retaining it in place.

Referring now specifically to the drawings, the numeral 10 generallydesignates a lock incorporating lthe present invention therein. The lock10 includes a cylinder or body 12 of conventional construction togetherwith a rotatable barrel 14 received within a longitudinal bore 16 withinthe cylinder 12. This much of the structure is conventional in natureand .the present invention may be incorporated into any type of locksuch as a pin-type lock, a wafer lock or any other mechanical .typelock. The structure has been illustrated in a pin-type lock for thepurpose of describing the purposes and functions thereof.

The cylinder 12 is provided with a plurality of radial passages or bores'18 which may vary in number. Normally, each of the passages 18 includesa cylinder pin 20 that is spring biased inwardly by light coil springs22.

The barrel 14 includes a plurality of passages 24 .therein whichcommunicate with a longitudinal bore or passageway 26 for receiving theblade or shank 28 of .a key 30 which has an irregular surface 32 thereonfor registry with sliding tumbler pins 34 so that the outer ends of thepins 34 will engage the ends of the pins 20 and due to the irregularityof the surface 32 and the variable length of the pins 34, all of thepins 34 Iand 20 will have their juncture coincident with the shear line36 between the -body and the barrel so that the barrel may then berotated in a conventional manne-r. Up to this point in the description,the structure has been conventional and itis the intent of the presentinvention to be incorporated into a rather conventional pin lock of the:type illustrated with very little modification thereof.

Essentially, the present invention involves the use of a floatingcylinder pin 38 in one of the passages 18 and, as illustrated, it ispreferable that the floating pin 38 be disposed adjacent the innermostspring-biased pin 20. However, the particular orientation of thelfloating pin 38 is not restricted insofar as it being used in lieu ofany one of the spring-biased pins 20, or, if desired, two or morefloating pins may be employed. In any event, the floating pin 38 isfreely movable within the passageway 18 and no spring is employed.

In alignment with the floating pin 38, the barrel is provided with anaccurately dimensioned tumbler pin 40 which is secured in place withinthe passage 24 by a piston 42 disposed substantially perpendicularthereto and slidably received within a sleeve 44. A calibrated coilspring 46 engaged the end of the piston 42 opposite from the pin 40 forurging the piston in frictional engagement with the pin 40. Preferably,the sleeve 44 is externally threaded as at 48 and is correspondinglythreaded into an internally threaded bore 50 formed in the barrel 14. Itis pointed out that the sleeve 44 may be secured in place by other meansthan threading and the spring may be secured in the sleeve in anysuitable manner with the spring 46 being of suilicient strength to causethe piston 42 to frictionally engage the pin 40 to prevent the movementof the pin during normal vibrations and the like encountered by thelock. However, upon application of longitudinal force on the bottomrounded end of the pin 40, it will be forced upwardly thus c-ausing theupper end thereof to move upwardly beyond the shear line 36 into thepassageway 18 which receives the floating pin 38 thus serving to preventrotation of the barrel and also serving to prevent longitudinalextraction of the barrel in relation to the body.

The frictionally retained pin 40 is also provided with lan undercutportion or notch 52 that is normally disposed inwardly of the point ofengagement between the piston 42 n.3 and the pin 40. However, when thepin 40 is moved outwardly, the piston 42 will be forced into the notch52 thereby locking the pin 40 outwardly beyond the shear line to preventthe pin 40 from being retracted without completely destroying the lock.Thus, regardless of how the pin 40 is moved outwardly, either by animproper key or by a lock picking tool, it will be retained in itsoutward position Ythus serving to prevent operation of the lock eventhough the proper key is subsequently used thereby indicating to theowner or possesser of the proper key that the lock has been tamperedwith.

Any one of the tumbler pins can be used as a master pin but it isrecommended that the next to last pin in the tumbler barrel be chosen asthe master pin to exert pressure thereon. The correct key for this lockwill be cut so that it clears the master pin by at least one fifteenthousandsof an inch. Therefore, when the correct key is inserted to openthe lock, it will not activate the master tumbler pin 40 and cannottrigger the piston 42 in the cylinder or sleeve 44. As illustrated inthe drawings, the master tumbler pin 40 is held in place precisely atthe shear line of the lock by the pressure exerted on it by the piston42. The floating cylinder pin also comes to rest precisely at the shearline of the lock by gravity and is held there by the support of thernaster tumbler pin 40 beneath it. As the correct key is inserted, itclears the master tumbler pin 40 and as it turns, the master cylinderpin 40 does not interfere with operation of the lock. However, when anykey but the correct key is inserted or when any picking device isinserted in the keyway and does not clear the master cylinder pin 40,the master cylinder pin 40 is raised. This action enables the piston 42to enter the notch and the pin 40 then will be retained in elevatedposition. Thus the master tumbler pin is locked with part of the pinprotruding above the shear line of the lock and in this position thebarrel cannot be turned nor retracted and, Vof course, the lock cannotbe opened. Even if a correct key is inserted after this, the lock stillcannot be operated thus indicating to the person with the correct keythat the lock has been tampered with.

The master cylinder pin 3S above the master tumbler or barrel pin 40 isconstructed of a length that will not permit the master tumbler pin 40to be raised completely above the shear line. Thus, with the mastercylinder pin 38 preventing the master tumbler pin 40 from raising abovethe shear line, and the side piston 42 preventing the master tumbler pin40 from dropping below the shear line, the master tumbler pin 40 remainswith a portion of its length above the shear line, and a portion of itslength below the shear line, effectively preventing the lock from beingopened under any condition except by destroying the lock.

The pin 40 has a longitudinal groove 5ft therein of less radialdimension than notch 52 for receiving the rounded end 56 of the piston42 as illustrated in FIGURE 5. This construction enables the pin 4f) tomove outwardly beyond the shear line 36 and the piston 4Z will stilldrop into notch 52. The other end of the groove 54 will prevent thebarrel pin 40 from dropping into the keyway since the inward movement ofthe pin 40 is limited by the inner end 56 of piston 42 engaging theupper closed end of the groove.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention asclaimed.

What is claimed as new is as follows:

1. A pick-proof lock comprising a lock cylinder body having alongitudinal bore therein, a barrel rotatably journalled in said bore,said body having a plurality of radial passages communicating with thebore, a pin slidably disposed in each of said passages, and at least oneof said pins floating within its Ipassage and the other of the pinsbeing spring-biased towards the bore for projecting into the bore, saidbarrel having a peripheral surface defining a shear line with said bore,said barrel including a plurality of passages therein alignable with thepassages in the body for receiving the inner ends of the pins mounted inthe passages in the body when the lock barrel is in locked condition,each of the bores in the barrel having a slidable pin therein, saidbarrel having a longitudinal passage therein communicating with thepassages having the pins therein for receiving a key having a particularirregular surface thereon for engaging the inner ends of the pins in thebarrels for urging them outwardly so that the outer ends of the pinsalign with the shear line for enabling rotation of the barrel when theproper key is inserted, means releasably securing the pin in the barrelalignable with the fioating pin in the body immovable for retaining thefloating pin in the body aligned with the shear line whereby thefioating pin will normally not serve to prevent rotation of the barrel,said pin in the barrel alignable with saidfloating pin being movableupwardly and away from. the key receiving passage in the barrel when animproper key or lock pickv ing tool is inserted in the key receivingpassage whereby the means retaining the pin alignable with the floatingpin will retain the pin above the shear line thereby preventing rotationof the lock barrel and at the same time indicating to a subsequent userof a proper key that the lock has been tampered with inasmuch as themeans for retaining the pin alignable with the floating pin will retainthe pin within the passage in the body receiving the fioating pin.

2. The structure as defined in claim. 1 wherein said means for retainingthe pin alignable with the iioating pin in place includes a pistonmember disposed generally in perpendicular relation to the longitudinalaxis of the pin, and spring means urging said piston member intoengagement with the side surface of the pin alignable with the floatingpin for retaining the pin frictionally in place.

3. The structure as defined in claim 2 wherein said pin alignable withthe floating pin includes a recess therein normally misaligned with thepiston but being aligned with the piston when the pin alignablerwith theiioating pin is moved by an improper key or by a lock picking toolwhereby the piston will engage the recess for securely retaining the pinoutwardly of the shear line for locking the barrel to the body therebypreventing rotation of the barrel and also preventing extraction of thebarrel from the body without destruction of the lock.

4. The structure as defined in claim 3 wherein said floating pin andsaid pin alignable with the floating pin are disposed adjacent theinnermost set of pins in the body and barrel.

5. The structure as defined in claim 4 wherein said barrel is providedwith a laterally extending bore communicating with the passage receivingthe pin alignable with the floating pin, a sleeve screw-threaded intosaid bore and slidably receiving said piston, said spring meansincluding a spring disposed within the sleeve for urging the pistonoutwardly thereof into frictional engagement with the pin alignable withthe fioating pin.

6. In a lock including a stationary part and a movable part, first lockmeans interrelated to the parts for lockingl the parts in relation toeach other until the first lock means is correctly manipulated forrendering the first lock means ineffective, and wholly independentsecond lock means interrelated to the parts and normally ineffective torender the parts locked in relation to each other and rendered effectiveto lock the parts together when the first lock means is incorrectlymanipulated and being continuously effective to lock the parts togethereven when the first lock means is subsequently correctly manipulated.

7. The lock as dened in claim 6 together with means for retaining thesecond lock means in its ineffective and effective conditions wherebythe parts will be retained in locked relation to each other when thesecond lock means is rendered effective.

8. The lock as dened in claim 7 wherein said second lock means includesa pair of pins normally having a juncture line coincident with the shearline between the movable and stationary parts, said juncture linesbetween the pins being misaligned with the shear line upon incorrectmanipulation of the rst lock means, said means retaining the second lockmeans in effective condition including a spring biased piston movablymounted in said movable part and engaged with one of said pins forretaining it in position bridging the shear line thereby preventingmovement of the movable part in any direction.

References Cited by the Examiner UNITED STATES PATENTS 758,024 4/ 1904Taylor 70-421 5 1,707,922 4/1929 Pepper 70-421 2,137,504 11/1938OkC-onnell 70-364 2,836,973 6/1958 Schillizzi 70-421 3,099,151 7/1963Schlage 70-383 3,195,330 7/1965 Bauer 70-421 10 PATRICK A. CLIFFORD,Primary Examiner.

ALBERT H. KAMPE, Examiner.

P, TEITELBAUM, Assistant Examiner.

6. IN A LOCK INCLUDING A STATIONARY PART AND A MOVABLE PART, FIRST LOCKMEANS INTERRELATED TO THE PARTS FOR LOCKING THE PARTS IN RELATION TOEACH OTHER UNTIL THE FIRST LOCK MEANS IS CORRECTLY MANIPULATED FORRENDERING THE FIRST LOCK MEANS INEFFECTIVE, AND WHOLLY INDEPENDENTSECOND LOCK MEANS INTERRELATED TO THE PARTS AND NORMALLY INEFFECTIVE TORENDER THE PARTS LOCKED IN RELATION TO EACH OTHER AND RENDERED EFFECTIVETO LOCK THE PARTS TOGETHER WHEN THE FIRST LOCK MEANS IS INCORRECTLYMANIPULATED AND BEING CONTINOUSLY EFFECTIVE TO LOCK THE PARTS TOGETHEREVEN WHEN THE FIRST LOCKS IS SUBSEQUENTLY CORRECTLY MANIPULATED.